Artist’s conception of the dusty, doughnut-shaped object surrounding the supermassive black hole, disk of material orbiting the black hole, and jets of material ejected by the disk, at the centre of a galaxy. Image credit: Bill Saxton/NRAO/AUI/NSF
Astronomers used the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) to make the first direct image of a dusty, doughnut-shaped feature surrounding the supermassive black hole at the core of one of the most powerful radio galaxies in the Universe — a feature first postulated by theorists nearly four decades ago as an essential part of such objects.
The scientists studied Cygnus A, a galaxy some 760 million light years from Earth. The galaxy harbours a black hole at its core that is 2.5 billion times more massive than the Sun. As the black hole’s powerful gravitational pull draws in surrounding material, it also propels superfast jets of material traveling outward at nearly the speed of light, producing spectacular “lobes” of bright radio emission.
Black hole-powered “central engines” producing bright emission at various wavelengths, and jets extending far beyond the galaxy are common to many galaxies, but show different properties when observed. Those differences led to a variety of names, ...